Iran made a significant conciliatory gesture towards the Obama administration today, offering to help US-led efforts to stabilise and rebuild Afghanistan.

At an international conference on Afghanistan at The Hague, in the Netherlands, the Iranian delegate, Mohammad Mehdi Akhundzadeh, responded positively to Barack Obama's new strategy for winning the war against the Taliban.

"Welcoming the proposals for joint cooperation offered by the countries contributing to Afghanistan, the Islamic Republic of Iran is fully prepared to participate in the projects aimed at combating drug trafficking and plans in line with developing and reconstructing Afghanistan," Akhundzadeh, one of Iran's deputy foreign ministers, said, according to an early text of his remarks provided by Iranian officials.

Akhundzadeh, whose mere appearance at the conference was seen as progress in US-Iranian relations – repeated Tehran's earlier criticism of the Nato role in Afghanistan saying: "The presence of foreign forces has not improved things in the country and it seems that an increase in the number of foreign forces will prove ineffective, too."

But he added: "The military expenses need to be redirected to the training of the Afghan police and army, and Afghanisation should lead the government-building process" – an apparent nod towards the Obama administration's decision to send 4,000 more US military trainers.

Hillary Clinton, the US secretary of state, said Washington wanted Iranian help with border security and counter-narcotics operations. The emerging new US policy on Iran emphasises the search for common ground between the two countries, rather than allowing the relationship to be entirely paralysed by the standoff over Iran's nuclear programme.

"How can you talk about Afghanistan and exclude one of the countries that's a bordering, neighbouring state?" Richard Holbrooke, the US special representative for Afghanistan and Pakistan, told reporters. "The presence of Iran here is obvious."

Iran has long sought recognition of, and help for, its struggle with drug traffickers along its long border with Afghanistan and Pakistan, which kills scores of troops and border police.

The Hague conference, which brought together Nato troop-contributing countries and Afghanistan's neighbours, also focused on the struggle to combat corruption in the Kabul government. Clinton described corruption as a "cancer" as menacing to Afghanistan's long-term future as the Taliban.

Afghanistan's president, Hamid Karzai, said progress had already been made in curbing graft in his government, and pledged to take part in a new "compact" with the international community. This arrangement, laid out in the new US strategy, sets benchmarks for transparency and accountability as conditions for further aid.